Using a Multimeter McTigue Junior High Technology Ed. Click Here D. Tracey Instructor

In this tutorial you will learn to: Understand what a multimeter is used for Identify the parts of a multimeter select the correct measuring range Measure DC voltage Measure DC current

It is a great tool to trouble shoot a faulty circuit. Multimeters are tools used by people to make electrical measurements in systems. It is an expensive piece of equipment and should used carefully and never dropped. A multimeter can be used to measure : Currant Voltage Resistance It is a great tool to trouble shoot a faulty circuit.

Parts of a Multimeter Test leads Display Probe Dial Connector Sockets To connect a multimeter to an electrical circuit a pair of test leads are used. One is black and one is red. (see picture) Each lead has a connecting plug on one end that allows the lead to be connected to the meter and a fine pointed probe on the other used to ‘probe’ the circuit. The leads are connected to sockets on the front of the multimeter. The sockets to be used depend upon the type of measurement to be taken A selector dial on the front of the multimeter allows you to specify what type of measurement to be taken and the range to be set The readings will show up on the display Probe Dial Connector Sockets

Using your multimeter Set dial to 20 volts If you have your multimeter in front of you plug the leads into the sockets on the front of the meter. The black lead plugs into the ‘Com’ socket. The red lead plugs into the ‘V-Ohm’ socket. The selector dial on the front of the multimeter allows you to specify what type of measurement is to be taken and allows the range to be set. Turn on the multimeter and set the dial to 20 as shown in the picture on the right. You set the dial at 20 because we will be measuring less than 20 volts.

Using the multimeter to determine DC voltage You will need your meter and two AA batteries for this lesson In this step we will use the meter to determine the voltage of a ‘AA’ battery When measuring voltage the multimeter probes must always be connected across the component in a circuit. The red probe must be connected to the positive side of the battery while the black probe must be connected to the negative side. (the battery has a + sign on the positive side and a – sign on the minus side. Set the selector dial to 20 volts When the black probe touches the negative end and the red probe touches the positive end the amount will show on the display Click on the amount below that closely matches the display on your meter 1.5 v 2 volt 1 volt

Click the blue box to go back to the slide that has the choices Sorry, you must have your lead wires on the wrong parts of the battery. Try another arrangement- red on the positive end and black on the negative end like in the picture below Click the blue box to go back to the slide that has the choices + end (has the bump Negative end, no bump

You used the meter correctly Good Job! You used the meter correctly Click on the arrow to continue

In this step try taping two AA batteries together length wise and putting the probes to each end like the previous task. The picture below will help. What voltage did your meter read? 3 1.5 2.5

Yes that correct! Keep up the good work.

In this step you will use the Basic Electricity Trainer Module Step 1. Turn on the power switch in the upper left hand corner of the module. Step 2. Place a yellow connector plug between the two pictures of the six volt batteries as shown in the picture on the right Place the red probe on the positive terminal of the battery picture and the black probe on the negative as shown in the picture Read the display on the multimeter. What does your display read? Basic Electricity Trainer Module Power switch 6 v 12 v 18 v Yellow connector plug

Sorry You must be having trouble with your probes. Remember- red probe on the positive and black probe on the negative and hold it tight. Click the blue button to go back to the problem

Sorry… Take another look at the picture to see if you have everything set up correctly Click on the button to go back to the problem

Excellent! I believe you have mastered using the voltage meter Click button to continue

In this lesson you will use the multimeter to determine DC current Step 1. To use the multimeter to determine current, measured in amps or milliamps you must first place the black wire in the socket marked COM and the red wire in the socket marked A or 10 A as shown in the picture Step 2. You must then turn the selector dial to the position labeled 200 M or 200 milliamps Step 3. Current is always measured in a circuit so the red and the black probe when hooked up to the circuit complete the circuit. The next picture will show this Click to move on Set dial to 200m as shown here Place the red probe into the socket labeled A as shown here

Here you can see how the meter is hooked up so it completes the circuit. Using you multimeter and Electricity Trainer wire the circuit as shown using a six volt battery, a motor, one blue connector wire going from the battery to the motor and your meter to complete the circuit. Turn on the power to the trainer and note the reading on your multimeter. Pick the reading below that best matches your reading. 18 42 95

Yes! That is correct. Thank you for your hard work and sticking with this tutorial Click here

Sorry… Click the button to go back to the last slide and double check your wires to see if they match up with the picture

Congratulations! This completes your tutorial in using the multimeter. You have learned to identify the various parts of a multimeter You know which sockets to use for measuring voltage and which sockets to use for measuring amperage or current. You’ve learned how to use the meter to determine voltage You’ve learned how to measure current. Congratulations! Click to end the tutorial Click here if you wish to go to the beginning